918
FXUS65 KBYZ 270719
AFDBYZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BILLINGS MT
119 AM MDT SAT JUN 27 2026
KEY MESSAGES
- SEVERE THUNDERSTORMS ARE EXPECTED TO IMPACT MUCH OF THE AREA
TODAY. THERE IS A RISK LEVEL 3 OF 5 FOR SEVERE STORMS EAST OF
ROSEBUD COUNTY. MAIN HAZARDS ARE LARGE HAIL AND STRONG WIND
GUSTS WITH HEAVY RAIN BEING A SECONDARY THREAT.
- SHOWERS AND THUNDERSTORMS AGAIN SUNDAY. SEVERE STORMS ARE NOT
EXPECTED.
- SNOW IS LIKELY IN THE MOUNTAINS ABOVE 8300 FEET SATURDAY NIGHT
INTO SUNDAY NIGHT, WITH ACCUMULATIONS OF 1-2".
- WARMING AND DRYING TREND NEXT WEEK.
DISCUSSION
THROUGH NEXT SATURDAY...
THE STORM PREDICTION CENTER HAS ISSUED A LEVEL 3 OUT OF 5 THREAT
FOR SEVERE STORMS FOR LOCATIONS EAST OF ROSEBUD COUNTY TODAY. THE
THREAT DECREASES TO THE WEST WITH LOCATIONS FROM BILLINGS WEST
BEING IN A LEVEL 1 OF 5 THREAT. 500 MB TROUGHING TO OUR WEST WILL
CREATE SURFACE LOW PRESSURE OVER WYOMING HELPING TO ADVECT
MOISTURE INTO THE REGION BEFORE BRINGING A COLD FRONT THROUGH IN
THE AFTERNOON. HRRR SOUNDINGS INDICATE STRONG CAPPING IN THE
MORNING BEING OVERCOME BY STRONG LOW AND MID LEVEL LAPSE RATES BY
EARLY AFTERNOON. STRONG INSTABILITY IS EXPECTED IN THE HIGHEST
RISK AREAS WITH CAPE VALUES IN THE 1-2,000 J/KG RANGE AND 0-6 KM
SHEAR IN THE 40-50 KT RANGE.
MODELS ARE TURNING THESE ENVIRONMENTAL FACTORS INTO STRONG STORMS
FOR MUCH OF THE AREA. THE LATEST HREF RUN SHOWS HELICITY TRACKS
MOVING OFF THE BIGHORN MOUNTAINS AND STRENGTHENING OVER SOUTHEAST
MONTANA. THE SOUTHWEST TO NORTHEAST SHEAR PROFILES THAT ARE
EXPECTED TODAY INDICATE STORMS STARTING OUT DISCRETE BEFORE
EVOLVING INTO MCS LIKE STRUCTURES. SOME DETERMINISTIC MODELS SUCH
AS THE HRRR INDICATE A BOWING MCS STRUCTURE OVER SOUTHEAST MONTANA
BRINGING WIND GUSTS IN EXCESS OF 50 KTS. ALL WEATHER THREATS WILL
BE IN PLAY TOMORROW INCLUDING WEAK TORNADOES, HAIL >2.0 INCHES,
WIND GUSTS >70 MPH, AND HEAVY RAIN.
SUNDAY WILL SEE CHANCES (40-60%) FOR SHOWERS AND THUNDERSTORMS
NORTH AND WEST OF A LINE FROM RED LODGE TO MILES CITY. SEVERE
STORMS ARE NOT LIKELY. PRECIPITATION CHANCES (40-70%) LINGER
MONDAY WITH SHOWERS AND GENERAL THUNDERSTORMS EXPECTED. SNOW
LEVELS ARE EXPECTED TO GET LOW ENOUGH (~8,000 FT) SUNDAY AND
MONDAY TO ALLOW 1-2 INCHES OF SNOW TO ACCUMULATE IN THE
ABSAROKA/BEARTOOTH MOUNTAINS. TUESDAY THROUGH SATURDAY IS EXPECTED
TO BE WARMER AND DRIER WITH TEMPERATURES INCREASING FROM THE 60S
AND 70S F SUNDAY AND MONDAY TO THE 80S F BY WEDNESDAY. TORGERSON
AVIATION
06Z DISCUSSION...A FEW WAVES OF SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS WILL CONTINUE TONIGHT INTO TOMORROW MORNING,
TRACKING SOUTHWEST TO NORTHEAST ACROSS THE FORECAST AREA. MAIN
THREAT WITH THIS ACTIVITY WILL BE LOCALIZED WIND GUSTS TO 35KTS
AND BRIEF HEAVY DOWNPOURS, BUT DO NOT EXPECT REDUCTIONS IN FLIGHT
CATEGORY BELOW VFR. UPPER LEVEL SYSTEM PUSHES CLOSE ENOUGH TO THE
AREA BY LATE MORNING SATURDAY TO GENERATE WIDESPREAD SHOWER AND
THUNDERSTORM ACTIVITY, STARTING IN THE WEST AND SPREADING EASTWARD
THROUGH THE DAY. MVFR CEILINGS AND VISIBILITY DOWN TO 2SM ARE
FORECAST WITH THE HEAVIER SHOWERS/THUNDERSTORMS THROUGH MID
EVENING TOMORROW. THERE IS AN ENHANCED RISK FOR SEVERE STORMS OVER
SE MT STARTING AROUND 20Z WITH GOLF BALL SIZE HAIL AND GUSTS OVER
60KTS, ALONG WITH TORRENTIAL RAINFALL, THE MAIN THREATS. A JET
INDUCED DRY SLOT PUNCHES UP INTO THE AREA FROM THE SOUTH MID
EVENING PUSHING CONVECTION NORTHEAST OF THE AREA AND LEAVING
MAINLY DRY VFR CONDITIONS OUTSIDE OF THE IMMEDIATE WESTERN
FOOTHILLS (KLVM) AND MOUNTAINS WHERE SHOWER ACTIVITY WILL
CONTINUE. CHAMBERS
PRELIMINARY POINT TEMP/POPS
TDY SUN MON TUE WED THU FRI
-------------------------------------------------------
BIL 075 052/068 049/068 051/077 052/081 055/087 059/089
9/T 82/T 25/W 31/U 12/T 10/B 11/B
LVM 068 042/058 040/058 041/071 043/076 046/081 049/082
8/T 96/T 78/T 53/T 23/T 32/T 22/T
HDN 077 050/072 047/071 049/078 050/083 053/090 057/091
7/T 81/N 26/W 21/U 11/B 11/U 11/U
MLS 081 054/073 050/071 052/077 053/083 056/090 061/092
4/T 72/N 15/W 21/U 11/B 10/U 11/U
4BQ 081 054/075 051/074 052/078 053/084 057/091 061/095
6/T 41/B 24/W 11/U 11/U 11/U 11/U
BHK 085 052/076 049/073 049/077 051/084 054/089 058/093
3/B 51/B 44/T 21/N 12/T 11/U 11/U
SHR 074 046/072 044/072 045/075 046/081 050/088 054/091
7/T 52/B 33/W 12/T 12/T 01/U 01/U
BYZ WATCHES/WARNINGS/ADVISORIES
MT...NONE.
WY...NONE.
WEATHER.GOV/BILLINGS
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